The Innovation Team at Agricultural Microbial Resources has systematically summarized the efficient colonization mechanisms of beneficial endophytic or PGPR (Plant Growth-Promoting Rhizobacteria) in the early plant inoculation and their impact on plant microbial community assembly. This review proposes a new strategy: sequential inoculation during the seed and seedling stages, aiming to maximize the effects of microbes in agricultural production practice. The related article titled, "Early inoculation and bacterial community assembly in plants", was published in the Microbiological Research journal.

The article systematically reviewed recent research progress in introducing beneficial microorganisms into plant seeds or seedlings. Studies have shown that such early interventions can significantly alter the diversity and assembly structure of microbial communities during later plant development, as well as enhance the plant's environmental adaptability. The review also discussed the regulatory mechanisms of early colonizing microbes in the assembly of plant-associated bacterial communities and their ecological significance. In terms of microbial inoculation strategies, the review compared the differences in colonization ability and functional expression between endophytic and rhizosphere microbes as inoculants and analyzed the significant role of synthetic microbial communities in enhancing plant health and productivity. The review concluded with an innovative strategy: inoculating a synthetic microbial community (SynCom1) primarily composed of endophytic bacteria through seed coating at the seed stage; followed by inoculating a synthetic microbial community (SynCom2) composed of PGPR at the seedling stage through methods such as integrated irrigation with water and other fertilizer. This "sequential inoculation" approach helps overcome industrial bottlenecks such as the difficulty of effective colonization and unstable effects of microbial fertilizers, maximizing the efficacy of microbial agents, enhancing their persistence and application effects, and providing new insights for empowering plant breeding through microbes.

Wang Xing, a doctoral student at the Institute of Agricultural Resources and Regional Planning (IARRP) of the Chinese Academy of Agricultural Sciences (CAAS), is the first author of the review, with Dr. Zhang Xiaoxia and Professor Christopher Rensing from Fujian Agriculture and Forestry University as co-corresponding authors. Professor Li Yuyi from IARRP, CAAS, contributed to the writing of the review and provided guidance, while Professor Liu Yunpeng offered valuable suggestions for content improvement. The study received support from the National Key Laboratory for Efficient Utilization of Northern Arid and Semi-Arid Cropland.

Dr. Zhang's research group has long been engaged in systematic studies on the role of seed-associated and rhizosphere microbiota in promoting crop growth and enhancing crop stress resistance. Their research covers the selection of beneficial microbial resources for agriculture, microbial adaptive evolution, and the development of biofertilizers for saline-alkali land. Based on the early "sequential inoculation" strategy, the functional microbial agents developed through methods such as seed coating and integrated irrigation with water and fertilizer have been demonstrated in saline-alkali fields in regions such as Dongying, Ordos, and Handan showing significant effects.

Figure 1: Pathways of Early Inoculation Effects

Figure 2: Early "Sequential Inoculation" Strategy

Original Article Link: https://doi.org/10.1016/j.micres.2025.128141